Serious games (SG) are part of a range of technologies that can be used for children with Autism Spectrum Disorder (ASD). Typically, these games target communication skills, social interaction and speech. There are, however, few SGs for autistic children which have the aim of helping to moderate sensory hypersensitivity. This paper presents an SG which aims to target this area. A set of critical sounds was heuristically determined, and implemented in an interactive SG for reducing auditory hypersensitivity (i.e. over-sensitivity to environmental sounds) in children with ASD. The game, Sinbad and the Magic Cure, is designed for Android devices, and is intended for children aged 8-11.